Pressure fluid motor



May 19, 1936. E. G'GARTINv 2,040,844

RESSUREy FLUID MOTOR Filed Sept. 20, 1932.

Patented May 19, 1936 UNITED STATES PATENT OFFICE PRESSURE FLUID MOTOR Massachusetts Application September 20, 1932, Serial No. 634,008

18 Claims.

This invention relates to pressure fluid motors and more particularly to improvements in the fluid distribution means of such motors.

An object of this invention is to provide an im- 15 proved pressure uid motor. Another Object is to provide an improved fluid distribution means for a pressure fluid motor. A further object is to provide an improved valve mechanism for a pressure fluid motor. These and other objects will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form and two modifications thereof which the invention may assume in practice.

In this drawing,-

Fig. 1 is a central, longitudinally extending sectional View of the preferred illustrative embodiment of the invention.

Fig. 2 is a View similar to Fig. 1 showing the 20 valve and motor piston in a dilerent position.

Fig. 3 is a front end elevational View of the valve chest member.

' Fig. 4 is a fragmentary sectional View similar to Fig. 1 showing a modified form of valve mechanism.

Fig. 5 is a detail sectional view illustrating a further modified form of valve mechanism.

In the illustrative embodiment of the invention shown in Figs. 1 to 3 inclusive, there is shown a motor cylinder I having a bore 2 containing a reciprocatory motor piston 3. The motor piston is provided with a cylindrical extension 4 projecting forwardly through and guided in a reduced bore 5 formed in the integral front head 6 of the motor cylinder. Secured at 1 to the exterior of the cylinder is a head block 8 having a cylindrical rearward projection 9. Slidably mounted on the projection 9 is a sleeve-like support element I which controls a throttle valve I I, as hereinafter described. Formed within the head block 8 is a bore I2 within which the rear end of the motor cylinder is tted, and interposed between a shoulder I3 on the head block and the rear end surface I4 of the cylinder are cooperating abutting plates I and I6 which form the valve chest of the valve mechanism, the plates I5 and I6 being clamped in position against the rear end of the cylinder by the head block 8. Arranged at the rear side of the plate I6 and formed in the head block 8 is a pressure chamber I1, and uuid under pressure is supplied to this chamber under the control of the throttle valve II from a supply connection I8 through passages I9, 20 and 2|.

Now referring to the improved valve structure, it will be noted that formed in the Valve chest plate I6 is a valve chamber 22 having reciprocably mounted therein a lluid distributing valve 23 herein of the annular disc type. The valve chamber at the rear side of the valve communicates with the pressure chamber I1 through an 5 axial passage 24, while the valve chamber at the forward side of the valve communicates with the pressure chamber through an axial passage 25, transverse passage 26 and longitudinal passage V21. The rear side of the Valve chamber com- 1() muni'cates with the forward end of the cylinder bore through a pair of passages 28 formed vin the plates I5 and I 6 and longitudinal passages 29 formed in the cylinder, the passages 29 communicating with the cylinder bore through radial l15 ports 3Il. The forward side of the valve chamber communicates with the rear end of the cylinder bore through a pair of longitudinal passages 3|. Communicating with the cylinder bore intermediate its ends is a radial port 32 connected `2o to exhaust through passages 33, 34, annular groove 35 and port 36 communicating withthe atmosphere. The disc valve 23 is formed witha cylindrical sleeve-like peripheral portion 31 providing a guide for the valve and a transverse cen- '25 tral imperforate partition 38. When the valve 23 is in its rearward position shown in Fig. 1 the end surface of the annular llange 31 seats against the rear end of the valve chamber, thereby cuttingo communication between the passages 24 30 and 28, while when the valve is in its forward position shown in Fig. 2 the end surface .of the annular flange 31 is seated against the forward end of the valve chamber, thereby cutting ofl communication between the passage 25 and the `35 passages 3l. The end surfaces of the ange when in seated position provide a pressure differential whereby the valve is held ln either of its operating positions by line pressure acting on the opposing area of the valve.

In the modified form of construction shown in Fig. 4, the valve 40 is r'eciprocably mounted in a valve chamber 4I formed. in a valve chest plate 42 interposed between the Valve chest plate I5 and a disc-like end plate 43. In.- this constructio-n, the valve chamber communicates with the pressure chamber I1 through .an axial passage 44 formed in the plate 43. In this instance, the disc valve is formed with a cylindrical annular peripheral flange 45 providing a guide for the 50 valve and an inner annular flange 46, the central ange being formed on a transverse imperforate partition 41, the outer and inner annular flanges 45, 46 of the valve forming, at the opposite sides of the valve, annular chambers 48 and 49. When '5'5 the valve is in the position shown in Fig-4, the end surfaces of the annular flanges 45, 46 are seated against the rear end of the valve chamber, thereby cutting off communication between the passages 44 and 28, and at this time the annular chamber 48 in the valve is in communication with the pressure chamber I1 through restricted passages 50, Y5I) formed in the end plate 43. 'I'hese flanges when seated against one end or the other of the valve chamber provide a pressure differ- Vential whereby the valve is held in position by the line pressure acting on the opposing area of the valve. Passages 59', 50 corresponding substantially to the passages 50, 50, open from passage 26 into the right hand end of the valve chamber 4I. Otherwise this form of the invention is identical to the preferred form above described.

In the modified construction shown in Fig. 5, the valve mechanism and valve chest structure are identical to Y the form disclosed in Fig. Y l with the exception that the restricted passages 50,` 59 and 59', 59 are omitted, and when the valve is in its opposite positions the annular chambers V48,Y 49 in the valve are connected to the pressure chamber vI1 through the axial passages 44 and respectively and restricted passages 5I, 5I v Y and the throttle valve I I is held open by the slidable support I0 as shown, pressure fluid may flow through the supply connection I8, passages I9, 20, and 2I to the pressure chamber I1. At this time communication between the forward supply passages 29 and the pressure chamber I1 is cut off by the end surface of the flange 31 seating against the rear end of the valve chamber 22, and pressure fluid then flows through passages 21,

26 and 25 through the valve chamber past the forwardsurface of the valve andrlongitudinal passages 3I to the rearend of the cylinder bore, the pressure iiuid acting on the rear pressure area. of the motor piston toV drive the latter forwardly to effect its working stroke. At this time the pressure withinV the forward end of the cylinder bore is connected to exhaust through passages 32, 33, 34, groove 35 to Vpassage 36. As

Vthe motor piston moves forwardly, the rear edge of the piston overruns the exhaust passage 32, connecting the rear end of the cylinder bore to exhaust, and as a result the pressurewithin the rear end of the cylinder is substantially reduced. The line pressure flowing through axial passage 24 .to the valve chamber at the rear side of the valve overcomes the reduced opposing pressure acting on the front pressure area of the valve, and as a result the valve is thrown forwardly from the position shown in Fig. 1 to the position shown in Fig. 2. When the valve is in the position shown in Fig. 2, the end surface of the flange 31 is seated against the forward end of the valve chamber, thereby cutting off communication between the passageV 25 and the passages 3|, and pressure fluid then flows from the pressure chamber I1 through axial passage 24 through the valve chamber past the rear side' of the valve and through passages 28, 29 and ports 30 to the forward end of the cylinder bore, the pressure fluid acting on the forward pressure area of the motor piston to drive the latter rearwardly to effect its Vretraction stroke. nAt this time the pressure within the rear end ofthe cylinder bore is connected to exhaust through passages 32, 33, 34, groove 35 and exhaust passage 36. As the motor piston moves rearwardly, the forward edge thereof overruns the exhaust passage 32, connecting the forward end of the cylinder bore to exhaust, and as a result the pressure within the forward end of the cylinder bore and passages 29, 28 is materially reduced. At this time the` pressure fluid flowing frompressure chamber I1 through passages 21, 26, 25 to the forward end of the valve chamber acts on the forward pressure area sure flowing from the pressure chamber through the axial passage 44 and restricted passages 50, 50, the pressure .acting on the rear pressure area of the valve throwing the valve forwardly against the opposing reduced pressure. Pressure acting through passages 59', 59 also aids the rearward valve movement. Otherwise this form of the invention operates in a manner identical to that above described. Inthe modified form of construction shown in Fig. 5, the'valve operates in a similar manner, but in this instance the valve is Vthrown rearwardly from the position shown by the pressure flowing from the pressure chamber I1 through passages 21, 26,25 and passages15l formed in the inner valve flange 46, the pressure acting on the forward pressure area of the valve overcoming the opposing reduced pressure. The other passages 5I function during theopposite valve movement. Otherwise this form of the invention operates in a manner identical to the forms above described.

As `a lresult of this invention, it will be noted that an improved pressure fluid motor is pro-vided having improved fluid distribution means resulting in amore powerful and eflicient motor. It will further be noted that by the provision of the improved valve mechanism which is of an exceedingly simple character and by the improved pass-age arrangement disclosed, a powerful motor is obtained having a relatively high piston speed with a minimum pressure fluid consumption. These and other uses and advantages of the improved pressure fluid motor will beclearly apparent to those skilled in the art.

While there are in this application specifically described one form and two modifications thereof which the invention may assume in practice, it will be understood that this form and these modifications are shown for purposes of illustration and that the invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the ap- 'cesses on the opposite faces of thev valve, means 75 for supplying line pressurevto said concentric recesses, said valve being thrown in either direction by line pressure within the recesses on one face of the valve acting on one pressure area of the valve when a piston controlled reduced pressure in the recesses on the opposite side of the Valve acts on the opposing area of the valve.

2. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber alined with the cylinder axis, a valve reciprocable in said valve chamber and having concentric annular flanges on its opposite faces adapted to seat against the end walls of the valve chamber and forming concentric recesses on the opposite faces of the Valve, means for supplying line pressure to said concentric recesses, said valve being thrown in either direction by line pressure within the recesses on one face of the valve acting on one pressure area of the valve when a piston controlled reduced pressure in the recesses on the opposite face of the valve acts on the opposing area of the valve.

3. In a pressure fluid motor, -a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, an imperforate disc valve reciprocable in the valve chamber and having concentric annular flanges on its opposite faces adapted to seat against the end walls of the valve chamber and yforming concentric recesses on the opposite faces of the valve, means for supplying line pressure to said concentric recesses, said valve being thrown in either direction by the line pressure within the recesses on one face of the valve acting on one pressure area of the valve when a piston controlled reduced pressure in the recesses on the opposite face of the valve acts on the opposing area of the valve,

4. In a pressure fluid motor, a cylinder, a piston reciproc-able therein, and uid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of' the cylinder and having a valve chamber, a valve reciprocable in said valve chamber and having concentric annular flanges on its opposite faces adapted to seat against the end walls of the valve chamber and forming concentric recesses on the opposite faces of' the valve, means for supplying line pressure to said concentric recesses, said valve being thrown in either direction by the line pressure within the recesses on one face of the valve acting on one pressure area of the valve when a piston controlled reduced pressure in the recesses on the opposite 'face of the valve acts on the opposing area o-f the valve.

5. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, a valve reciprocable in said valve chamber and having concentric annular flanges on its opposite faces adapted to seat against the end walls of the valve chamber and fo-rming concentric recesses on the opposite faces of the valve, said valve being thrown in either direction by the line pressure within the concentric valve recesses on one face of the valve acting on one pressure area of the valve, when a piston controlled reduced pressure Vin the recesses on the other face of the valve acts on the opposing area of the valve, said valve having annular peripheral guide flanges,

concentric inner 4annular flanges and an imperforate transverse partition separating said flanges to form said concentric annular recesses on the opposite faces thereof.

`6. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber, said valve having concentric annular flanges adapted to seat against the oppositev end walls of the valve chamber and forming concentric recesses in the valve on the opposite faces thereof, and passage means connecting the rear side of the Valve chamber with the forward end of the cylinder, passage means connecting the front side of the valve chamber with the rear end of the cylinder, and passage means for supplying line pressure to the valve chamber at opposite sides of the valve, said recesses in said valve receiving line pressure from said last mentioned passage means.

7. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber, said valve having concentric annular flanges adapted to seat against the opposite end walls of the valve chamber and forming concentric recesses in the valve on the opposite faces thereof, and passage means connecting the rear side of the valve chamber with the forward end of the cylinder, passage means connecting the front side of the valve chamber with the rear end of the cylinder, passage means for supplying line pressure tothe valve chamber at opposite sides of the valve, said recesses in said valve receiving line pressure from said last mentioned passage means, and piston controlled exhaust passage means for reducing vthe pressure in said first mentioned passage means to effect throwing of the valve from its forward position to its rear position, the line pressure in said third mentioned passage means overcoming the opposing reduced pressure in said first mentioned passage means.

8. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest arranged at the rear end of the cylinder and having a valve chamber, said valve having concentric annular flanges adapted to seat against the opposite end walls of the valve chamber and forming concentric recesses in the valve on the opposite faces thereof, passage means connecting the rear side of the valve chamber with the forward end of the cylinder, passage means connecting the front side of the valve chamber with the rear end of the cylinder, passage means for supplying line pressure to the valve chamber at opposite sides of the valve, said recesses in said valve receiving line pressure from said last mentioned passage means, and piston controlled exhaust passage means for reducing the pressure in said first mentioned passage means to effect throwing of the valve from its forward position to its rear position, the line pressure in said third mentioned passage means overcoming the opposing reduced pressure in said first mentioned passage means, and said valve being thrown from its rear position to its forward position by the line pressure in said third mentioned passage means acting on the rear pressure area of the valve overcoming the opposing reduced pressure in said second mentioned passage means acting on the forward pressure area of the valve.

V9. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, a Vvalve reciprocable in said chamber and having Yconcentric annular flanges on its opposite faces adapted to seat against the opposite end walls of the valve chamber and forming concentric recesses on the opposite faces of the valve, axial supply passages for supplying pressure fluid to Vthe inner recesses in the valve, separate passages for supplying pressure fluid to the outer recesses in Ythe valve, said valve being thrownv in either direction by line pressure acting in the outer annular recess on one face of the valve when a piston controlled reduced pressure prevails in the outer annular recess onV the oppositeV face of the valve.

10. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, a valve reciprocable in said valve chamber and having on its opposite faces annular peripheral guide flanges adapted to seat against the opposite end walls of the valve chamber and recesses on the opposite faces of the valve, axial fluid supply passages communicating with the opposite ends of the valve chamber and said valve recesses, passages in the valve chest leading from the opposite ends of the valve chamber to the opposite ends of the cylinder and controlled by said valve, said valve being thrown in either direction solely by the line pressure within 'the recess on one face of the valve when a piston controlled reduced pressure prevails in the recess on the other face of the valve.V

11. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of Vsaid piston and including a valve chest having a valve charnber, an imperforate disc Valve reciprocable in said valve chamber and having a peripheral controlling-surface, said valve adapted to seat against annular seating surfaces on the opposite end walls of the valve chamber, axial fluid supply passagescommum'cating with the opposite ends of the valve chamber, passages leading from the opposite ends of the valve chamber to the opposite ends of the cylinder and controlled by said valve, said passages communicating laterally with the valve chamber wholly between the front and rear ends thereof and controlled by the surface of the valve periphery so that fluidk flows directly laterally from the valve chamber to said second mentioned passages, said valve being thrown in either direction solely by the line pressure in the valve chamber at one side of the valve when a piston controlled reduced pressure prevails in the valve chamber at the other side of the valve.Y

i2. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said Vpiston including a valve chest having a valve chamber, a valve reciprocable in said valve chamber and having on its opposite faces annular peripheral guide flanges adapted to seat against annular seating surfaces'on the opposite end Walls'of the valve chamber and forming recesses on the opposite faces of the valve, axial fluid supply passages communicating with the opposite ends of the valve chamber andsaid valve recesses, a passage leading from the forward end of the valve cham- -ber to the rear end-of the cylinder, a passage leading fromthe' rear end of Vthevalve chamber to the frontend of the cylinder', said last mentioned passages communicating with the valve chamber wholly between the endseof the latter and controlled by said valve, said valve being thrown in eitherV direction solely by the line pressure within the recess on one face-of 'the valve when a piston controlled reduced pressure in the recess prevails in the other face of thervalve.

13. In a pressure fluid motor, a cylinder, a pis-l ton reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber,

a valve reciprocable in said valve chamber andY having concentric annular flanges on each of its opposite faces adapted to seat against the end Walls of the valve chamber and forming concentric recesses on the opposite faces of the valve, axial fluid supply passages communicating with the inner recesses on the opposite faces Vof the valve, separate relatively-restricted passages for supplying pressure fluid to the outer recesses on the opposite faces of the valve, said valve being thrown in either direction by line pressure Within the recesses on one face of the valve acting on one pressure area of the valve when a piston controlled reduced pressure in the recesses on the opposite face of the valve acts on the opposing area of the valve.

14. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, a valve reciprocable in said valve chamber and having concentric annular flanges on each of its opposite faces adapted to seat against the end walls of the valve chamber and forming concentric recesses on the opposite faces of the valve, axial fluid supply passages communicating with the inner recesses on the opposite faces of the valve, relatively restricted passages formed in the inner flanges for conducting fluid from the inner recesses to the outer recesses on the opposite faces of the valve, said valve being thrown in either direction Vby line pressure within the recesses on one face of the valve acting on one-pressure area of the valve when a piston controlled reduced pressure in the recesses on the opposite face of the valve acts on the opposing area of the valve.

l5. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution Ymeans for effecting reciprocation of said piston including a valve chest comprising a plate having a circular recess in its forward face, afront plate directly abutting the forward face of said plate and forming a closure for the forward end of said recess, a disc Valve reciprocable in said recess and having a peripheral controlling surface, axial passages in said plates for supplying Y line pressure fluid to the opposite ends of said recess, lateral grooves cut in the sides of the recess wholly between the front and rear ends of said recess, and passages communicating with said grooves respectively for supplying fluid from said recess to the opposite ends of said cylinder, the peripheral controlling surface of said valve consaid lateral grooves.

16; In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest comprising a centralV plate having an axial bore, front and rear `end plates directly abutting the opposite faces of the centralplate and forming closures Vfor the ends Yof said axial bore,'a disc valve reciprocable in said axial bore and having a peripheral controlling surface, said valve engageable upon reciprocation thereof with the inner surfaces of the end plates, lateral grooves cut in the opposite faces of the central plate and communicating with the opposite ends of said axial bore Wholly between the ends of the latter, passages connecting said grooves respectively with the opposite ends of the cylinder, and axial passages in said end plates for supplying line pressure iiuid to the opposite ends of said axial bore, the peripheral controlling surface of sa-id valve controlling ow of pressure uid from said axial bore to said lateral grooves.

17. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, a valve reciprocable in said valve chamber and having formed in each side thereof a pair of recesses, fluid supply passages communieating with the opposite ends of said valve chamber and said valve recesses, passages in the valve chest leading from the opposite ends of the valve chamber to the opposite ends of said cylinder and controlled by said valve, said valve being thrown in either direction solely by the line pressure inA the recess at one side of said valve when a piston controlled reduced pressure exists in the recess on the other side of the valve.

18. In a pressure fluid motor, a cylinder, aV

piston reciprocable therein, and iiuid distribution means for effecting reciprocation of said piston including a valve chest having a valve chamber, a sleeve valve reciprocable in said valve chamber and having midway between its ends an imperforate transverse partition forming recesses in the opposite sides of the valve, said valve adapted to seat against the opposite ends of the valve chamber, axial fluid supply passages communicating with the opposite ends of the valve chamber and said valve recesses, passages in the valve chest leading from the opposite ends of the valve chamber to the opposite ends of the cylinder and controlled by said valve, said valve being thrown in either direction solely by the line pressure in the recess on one side of the valve when a piston controlled reduced pressure prevails in the recess on the other side of the valve. Y

ELMER G. GARTIN. 

